public class Notes.HeaderBar : Gtk.HeaderBar
{
    construct
    {
        // 标题
        title = "jarvis";
        // 副标题
        subtitle = "less";
        show_close_button = true;
        // 添加按钮
        var add_button = new Gtk.Button.with_label ("Add");
        pack_start(add_button);
    }
}
